Unable to import image as plane
Can you insert other objects, or is it only the plane that doesn't appear in your project? Also, as stated above you can always look for your plane in the Outliner (file browser in the upper right corner of the Default Blender view) for your imported plane. If it is in your outliner, select it and press "." to teleport to it. If it isn't, it may be a corrupted project file or plugin; in that case, simply start up a new project and see if you can import an image as a plane there instead.